Knee joint for artificial legs



Oct. 13, 1936. \Y J. J. McCANN 2,057,534

KNEE JOINT FOR ARTIFICIAL LEGS Filed Dec. 20, 1954 2 Sheets-Sheet 2 WITNFSSES:

5q INVENTOR:

J i]. M CAN/v. I I 7 C Patented Oct. 13, 1936 UNl'lED STATES PATENT OFFICE 2 Claims.

This invention relates to knee joints for artificial legs, and has for an object to provide means for more securely attaching the joint structure to the leg structure.

A further object of the invention is to provide a-joint structure having a shoulder strap connectionof greater efiiciency and reliability than heretofore known.

.A further object of the invention is to provide, in a knee joint structure, improved means for clamping the shell of the thigh socket at the joint.

The invention, therefore, comprises a bar which will form the axis of the joint, said bar being provided with an integral enlargement to which are secured arms carrying a roller for shoulder strap connection, and with discs carried upon said bar composed of parts clamped together by screw thread action, said parts being so constructed as to clamp an inclined or tapered margin of an opening formed through the thigh socket, and with arms rigidly connected to said bar for rigid connection with the shin section so arranged that the action of the shoulder strap upon the integral part will actuate the shin section.

The drawings illustrate an embodiment of the invention and the views therein are as follows:

Figure 1 is a view of the improved knee joint in side elevation shown applied to fragments of a thigh socket and shin section,

Figure 2 is a sectional view through the thigh socket and shin section, with parts of the joint shown in section,

Figure 3 is a View in side elevation of the joint disassociated from the leg sections,

Figure 4 is an exploded view of the joint members,

Figure 5 is an exploded view of the shoulder strap attaching parts,

Figure 6 is an enlarged detail view showing the connection of the thigh socket to the joint,

Figure '7 is a view partly in elevation and partly in section of one section of the clamping member,

Figure 8 is a view partly in elevation and partly in section of the companion clamping member,

Figure 9 is a view in end elevation of the member shown at Figure 7 and seen as indicated by arrow 9 at that figure, and

Figure 10 is a view in end elevation of the member shown at Figure 8 and is indicated by arrow H) at that figure.

Like characters of reference indicate corresponding parts throughout the several views.

The knee joint which forms the subject matter of this application is intended for association with an artificial leg part having a thigh socket 211 and a shin section 2|. These are shown at Figures 1 and 2 as composed of sheet material, preferably though not necessarily spun, but the invention is not limited to the particular type of material nor in any manner to its method of construction.

The joint itself comprises a bar 22 which is provided with an integral enlargement 23 to which are applied the lever members 24 journaling the shoulder strap roller 25.

The journaling of the roller may be as shown in the drawings, or in any approved manner, but the lever members 24 are provided each with an opening 26 properly proportioned to make snug fit upon the bar 22, and with a series of perforations 21 through which may be passed a bolt 28 which will also pass through the opening 29 in the enlargement 23, and being provided with a nut 30 will accommodate the adjustment of the levers 24 to various angular positions relative to the bar 22 and enlargement 23. By this construction a lever for the attachment of the shoulder strap is provided which will be free from noises and will not readily become displaced.

The ends of the bar 22 are provided with multiangular parts 3| and arms 32 are attached thereto by means of perforations 33 formed in said arms, and screws 34 for holding said arms in position.

Between the multi-angular ends 3| and the enlargement 23, a reduced part 22 is adapted to receive the joint members, and gaskets 35 at the shoulders are contemplated, but such gaskets are not essential. These joint members are identical upon opposite sides and the description of one is a description of both. It comprises a member 36 having a bore 31 properly proportioned to make easy fit upon the said section 22'. This member carries a ball bearing, shown as an entirety at 38, no particular stress being laid upon the ball bearing as such, but only its use in conjunction with the joint as an entirety.

The ball race member 39 is provided with a bore 43 properly proportioned to make snug fit upon the section 22' so that the stresses of the joint will be carried upon the ball hearing. The member 36 is provided with a cylindrical threaded part 4| and a conically inclined part 42 with an annular shoulder 43.

Cooperating with this part 36 is a ring 44 internally threaded, as at 45, for coaction with the threaded part 4| of the section 36. This ring 44 is provided with a conically inclined part 46 complementary to the inclination 42 of the memas by the rivets 52.

ber 36, and an annular rib 41 complementary to the annular shoulder 43.

The ring 65 and part 36 are adapted to clamp a conically tapered boss 48 formed about an opening through the thigh socket at the exact locus of the knee joint. By employing the recesses 49 in the section 36 a spanner may be used for tightening together the parts 46 and 36 to effectuate an efi'icient clamping of the thigh socket 20.

The arms 32 are also preferably bent at 5 and from the exterior of the shin section pass through perforations to the interior of the section to which section the arms are secured,

53 is applied at the posterior of the joint.

The operation of the joint will be no different from the operation of any joints now already well-known, the invention residing in producing a better type of any joint operable in the usual manner. It is believed that no space need be taken for further explanation of the operation.

course, the knee joint for artificial legs illustrated may be modified and changed in various wayswithout departing from the invention hereinset forth and hereinafter claimed.

Iclairnl- I 1. A knee joint comprising a journaling bar, a joint adjacent each end of the bar, each of said joints comprising an annulus having a bearing therein associated with the bar and with The usual, limiting member 7 a threaded cylindrical part, said annulus being further provided with a conically inclined area surrounding said threaded part with an annular shoulder continuing said tapered part to the perimiter, a ring part having complementary threads and complementary inclined end annular parts, a leg section having an opening therethrough, with a boss about said opening, said boss being inclined in consonance with the inclination of said conically tapered parts of the bearing member, and means to clamp the two parts of the bearing member rigidly upon the boss to clamp said boss between the conically inclined areas and the annular parts.

2. A bearing member for a knee joint, said member comprising a member having a ball bearing therein, said ball bearing being provided with an axial bore, the member being provided with a cylindrical part concentric with the bore and having external screw threads thereon, said member having a conically inclined part extending from said threaded section toward the perim.-. eter with an annular shoulder completing the distance from the conically inclined part to the perimeter, and, a coacting ring having complementary threads, conically inclined part, andzane. nular part adapted totform a clamping area between the parts, one section of said area being conically inclined, another section being formed on a radial plane.

JOHNJ. MCCANN. 

